swihart



Patented lune 20, I899.

No. 627,l52.

J. H. SWIHART.

COMPUTING SCALE.

(Application flied May 24, 1897.)

(No Model.) 2 Shoots-Sheet I.

No. 627,!52. Patented June 20, I899. J. H. SWIHART.

COMPUTING SCALE.

(Application filed May 24, 1897.)

2 Sheets$haat 2.

(No Model.)

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UNITED STATES PATENT QFFICE.

JOHN HENRY SWVIIIART, OF CLEVELAND, OHIO, ASSIGNOR TO THE NATIONALCOMPUTING SCALE COMPANY, OF SAME PLACE.

COMPUTING-SCALE.

' SPECIFICATION forming part of Letters Patent No. 627,152, dated June20, 1899.

Application filed May 24, 1897. Serial No. 637,900. We model.)

I To dZZ whom it may concern.

set or adapted to indicate values at diiferent rates.

The objects of the invention are to provide convenient andeasily-operated means for setting the scale, to diminish the possibilityof error in so doing, and to diminish the wear upon the scale.

The invention consists, broadly, in the combination with a rate-beam anda plurality of vertically-movable fulcrum-blocks adapted to be movedeach into engagement with a predetermined part of said rate-beam.

It also consists in the more specific combinations of parts, as pointedout in the claims.

In the drawings, Figure l is a front elevation of the upper part of acomputing-scale employing my invention. Fig. 2 is a sectional left endview on line 2 20f Fig. 1. Fig. 3 is an enlarged front view of themechanism embodying my invention. Fig. 4 is a sectional view of thefulcrum-supporting bar, showing one of the fulcrum-blocks; andFig. 5 isa plan view of the part of the-scale containing my invention.

The particular form of scale which I have chosen to illustrate myinvention is substantially that which is described in LettersPatout No.57 8, 784, granted toame March 16, 1897 but the invention is applicableto many forms of computingscales wherein the leverage of the rate-beamis varied by changing the fulcrum-point thereof.

Referring to the parts by letters, A represents one of the scale-beams,and a the connecting-rod wherewith it is connected with theplatform-levers, (which are not shown.)

This connecting-rod may be made of a lower section a and an upper link awhich is a well-known construction of scale connectingrods.

B represents the value-beam. C represents a horizontal rate-beam whichis suspended at its ends by the links H II from the beams A and B,respectively. The value-beam may be provided with a plurality of sets ofvalue-indicating figures bl), associated with the same orsimilarly-placed marks b whereby this beam will indicate values ateither of two rates corresponding with each f ulcru m-point on therate-beam. So much of the scale as is above described is substantiallylike that which is shown in the prior patent mentioned.

I) represents a horizontal rectangular bar which is secured to thebrackets F, and thereby held above and parallel with the rate-beam. Thebrackets are secured to some fixed part of the frame of the scale.

E E represent fulcrum-block s which are supported upon said bari'n suchmanner that theymay move vertically, but not otherwise. Movement alongthe bar may be prevented by shoulders 61 d at the ends of the series ofblocks and by placing said blocks in contact, as shown, near the leftend of' the bar D or by placing spacing-bloc'ks'e between them, asshown, near the ends of said bar. 'The bar D passes through rectangularslots e in the fulcrum-blocks. Each fulcrum-block is raised by a spring6 which is compressed between 'the top of bar D and the top of the slot.

The lower edge of each block E is adapted to engage with a definite partof the ratebeam. The edge of the rate-beam may have a plurality ofproperly-spaced knife-edges c, and the 'lower edge of each fulcrum-blockmay have a shallow groove e, in which the associated knife-edge engages;or, instead, the edge of the .beam 'may have properlyspaced notches,assho'wn in said prior patent, and each fulcrum-block may have aknifeedge like that on the single fulcrum-block shown in said priorpatent.

Associated with each fulcrum-block is a key-lever G, whichispivoted atits rear end to a horizontal bar K which bar is secured to the bracketsF. I Each key-lever passes over and engages with the top of acorresponds ingfulcrum-b1ock.' Upon each keyis placed a figure orfigures indicating the rate or rates at which the scale will be set ifsaid key is depressed and the corresponding fulcrumblock broughtintoengagement with the ratebeam. A latching device is provided for holdingthe key down until the completion of the particular operation for whichthe scale is set by the downward movement of the key. It is notessential to the invention, broadly considered, what form of latchingmechanism shall be used. The mechanism for this pur-v pose shown in thedrawings consists ofa rock-shat't I, to which is rigidly securedalatch-lever J, the length of Whichis equal to the entire distance fromthe outsidekey at the right to the outside key at the left. Thislatch-lever has a hook or shoulder j on its front face, and'above thisshoulder the lever is beveled backward. Each key-lever is providedwith adepending arm g, having. a similarly-shaped en'd-that is to say, an endhaving-a hook or shoulder gand a beveled portion below/the same. When,new, any key-lever is depressed,it.pushes this latchlever backward untilthe two shoulders pass each other, whereupon the latch-lever is swungforward, so that its shoulder 9 engages above the shoulder j onthe'key-lever, whereby the upward movement of the keylever is prevented.The latch-lever is moved automatically in the latching direction bymeans of a spring M.

I believe I am the first to devise a computing-scale wherein is employeda plurality of fulcrum-blocks each of which may be'moved into contactwith a predetermined part of the rate-beam. I do not, therefore, intendor wishto limit the invention to the specific 'em-' bodiment shownfurther than is expressed in the claims.

It is desirable to prevent any movement of v the beams even when a loadis put upon the scale-platform until after the scale has been set. Ihave shown in the drawings mechanism for attaining this result. I

A vertically-sliding plate N is held against lugs ff on the left bracketF by means of screws n, which pass through vertical slots n in theplate. The plate is permitted to move,but is guided in its movements bythese slots and screws, On this plate is-a pin 11*, which projects underacross-bar a which is an integral part of the link a. When the plate Nis down, this pin does not interfere with the movement of the link; butwhen the plate is raised this pin engages with the crossbar a and holdsthe link a up. This plate is moved np.and down'by a toggle deviceconsisting-of the bent lever T, which is pivoted to the bracket F, and alink t, which is pivoted to the lever T and to the plate N. Whenthehandle end of the lever is moved down, the plate is raised, with theresult before stated. By moving the toggle-link just over the center theplate is held up. A pin n on the plate, with which the link 25 engages,limits this movement over the center. This same APin j on' thelatch-lever lies above tltis camlug. When the plate N is raised, thecamlug r strikes this pin, and since the lever B cannot rock (beingprevented by pin '21.) the latch J is pushed forward, with the result ofrelieving any key-lever'which it was holding down. hen the plate movesdown, the cam again strikes this pin; but in this case the lever Rswings forward until the cam-lug passes over said pin,when the leverfalls. by gravity into position to again operate as described.

Having described my invention, Iciaim- 1. In' a computing-scale, thecombination ofa horizontal rate-beam incapable of any substantialendwise movement, with a plurality. of fulcrum-blocks immovablelengthwise of said rate-beam but adapted to be separately movedtransversely of the beam into and out of engagement therewith, and eachwith a difierent but definite point thereon, substantially as specified.g

2. In a computing-scale, the combination of a horizontal ratebeam, aplurality of fulcrum-blocks which are incapable of endwise movementrelative to saidbeam, but are movable transversely of said'bea'm intoand out of engagement therewith at diiierent but definite points, andmeans for severally holding said fulcrum-blocksimmovable when in vengagement with said beam and during the operation of the scale,substantially as speci- V fied. 3. In a computingscale, the combinationof the rate-beam ,a plurality of vertically-mow able fulcrum-blocks, anda key-lever associated with each fulcrum-block whereby said block ismoved into engagement with the rate-beam, substantially as described.

4. In a computing-scale, the combination with a rate-beam, a horizontalguide-bar, a

plurality of vertically movable fulcrumblocks which embrace saidguidabar, springs rality of key-levers, each associated with afulcrum-block and adapted. to move it into engagement with therate-beam,substantiall y as described.

5. In a computingscale, the combination of a rate-beam, a plurality ofvertically-movable firlcrum-bldcks, a plurality of key-levers ing devicefor holding down the depressed key-levers, substantially as described.

6. In a computing-scale, the combination -f0r'raising saidfulcrum-blocks, and a plu-,

of a rate-beam, a plurality of vertically-movable fulcrum-blocks adaptedto be separately moved into engagement therewith,a plurality ofkey-levers each adapted to so move said f ulcr u iii-blocks, eachkey-lever having a beveled hook on its under side, and a beveled,

latcl1lever having'a shoulder which is adapted to engage withahook-latch on the key-lever, and latch-releasing mechanism,substantially as'described, p

7. In a computing-scale, the combination of a rate-beam, a plurality ofvertically-mov able fulcrum-blocks, with a plurality of keylcvers, onefor moving each fulcrum-block, and mechanism for preventing the movementof the computing mechanism until afterithe scale is set by-theengagement of one of the fulcrum-blocks with the rate-bean1,substantially as described. 7

S. In a computing-scale, the combination of a rate-beam, a plurality ofvertically-movable fulcrum-blocks, an equal number of keylevers adaptedto operate the several fulcrumblocks, and a latching device for holdingdown the depressed key-levers, with a vertically-movable plate whichwhen in. its raised position prevents the operation'of the com-- pu tingmechanism, and means carried by-said plate for releasing said latch whenmoving upward, substantially as described.

9. In a computing-scale, the combination oi" the connecting-rod, whichconnects the computing mechanism with the load, saidconnectingnorhhavinga cross-bar a with a vertically-sliding plate havinga pin which lies below said cross-bar, and means for raising said plateto cause said pin to engage with the cross-bar, substantially asdescribed.

10. In a computing-scale, the combination of the beams A and 13, thehorizontal ratebeam suspended from said two beams by f reeiy-swingin glinks, the connecting-rod having a cross-bar a and means for changingthe fulcrum-point of the rate-beam, with a verticallymovable pin lyingbelowsaid crossbar, and mechanism for moving said pin up into engagementwith the cross-bar, substan= tially as described, 7

1,1. Ina computing-scale, the combinatiom of a rate-beam,mechanisn1,which includes a vertical connecting-rod, for transmittingmotion from the platform-levers to the ratebeam, aplurality ofvertically-movable fulcrum-blocks, an equal number of key-levers foractuating the fulcrum-blocks,and a springlatch which is adapted to holddown the de= pressed key'-1evers,with a vertically-movable plate havinga pin which when the plate is raised is adapted to engage with said coneheating-rod and prevent its downward move-'60 nient, a lever pivoted tosaid plate and have ing a double-faced cam-lug, a pin on the latch withwhich said lug engages, a pin for limiting the movement of said lever inone direction, and mechanism for operating said plate, substantially asdescribed.

1 12. In a weighing and computing scale, the

combination of the scale-beam, with a loads-upp'orting mechanism, andconnections including a set of keys for determining at what distancefrom the fulcrum of said beam the load-supporting mechanism shall act,substantially as described.

13, In a computing-scale,- thecombination of the rate-beam, afulcrum-block and a piv-, i

